One vertex per element, one color per generator, with an edge from x to x·s.
(3,7)(6,8)(9,10,14,15)(11,18,17,13)(12,20,22,16)(19,21,23,24)(25,26,29,32)(27,33,35,30)(28,31,36,38)(34,39,40,37)(1,2)(3,6)(4,5)(7,8)(10,15)(11,17)(16,20)(19,23)(25,27)(26,30)(28,34)(29,35)(31,37)(32,33)(36,40)(38,39) involution — undirected(2,5)(6,8)(10,15)(11,17)(16,20)(19,23)(25,26,29,32)(27,30,35,33)(28,31,36,38)(34,37,40,39)(1,2)(3,6)(4,5)(7,8)(9,11,14,17)(10,13,15,18)(12,19,22,23)(16,21,20,24)(25,26)(27,30)(28,31)(29,32)(33,35)(34,37)(36,38)(39,40)(9,12,14,22)(10,16,15,20)(11,19,17,23)(13,21,18,24)(25,28,29,36)(26,31,32,38)(27,34,35,40)(30,37,33,39)(1,3)(2,6)(4,7)(5,8)(9,13)(10,17)(11,15)(12,21)(14,18)(16,23)(19,20)(22,24)(25,27)(26,30)(28,34)(29,35)(31,37)(32,33)(36,40)(38,39) involution — undirectedA Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.